Republican candidates square off at 9 p.m.Tuesday night in Milwaukee on Fox Business Channel for their fourth debate, this time with just eight people on stage. There are huge stakes for Jeb Bush as the former Florida governor risks further alienating donors if he doesn't have a much stronger performance.
Bush has had some good days with his new, more open, freewheeling media strategy in New Hampshire and Iowa but he could kill it all with a bad debate performance. One Wall Streeter put it to me simply: "He has to stop the death spiral in his poll numbers."
Ben Carson will also likely face some more questions about claims in his autobiography that don't fully hold up to scrutiny. Fox moderators have suggested they will not try and repeat CNBC's aggressive approach, so Carson may be able to get away with just beating up on the media some more, always a popular approach with Republican audiences.